This invention relates generally to tubular medical devices intended for insertion and extended stay within a body pathway. Relating more particularly to tracheal tubes such as endotracheal and tracheostomy tubes, the present invention is directed to the effective removal of secretions and the like which accumulate between the tracheal tube and the wall of the intubated pathway.
Conventionally, the tracheal tube comprises an elongated tubular device of resilient material, arcuate in its longitudinal extent, providing a wall which defines a continuous central fluid passage. When intubated within the breathing pathway, a forward segment and end resides in the trachea and a rearward segment and end resides outside the remainder of the breathing pathway, extending through the mouth, naris, or tracheostomy of a patient. A circumferentially expansible cuff is a predominate tracheal tube feature and resides near its forward end. Inflated to provide a seal with the tracheal wall, the cuff acts to prevent the escape of respiratory gasses exchanged between the tracheal tube and the lungs and, at the same time, functions to prevent a variety of substances which accumulate within and along the intubated pathway from entering the lower respiratory system.
As mentioned, secretions and other substances commonly accumulate between the tracheal tube and the inner wall of the intubated pathway and range from upper airway secretions, lower airway secretions "blown" upward past the cuff during paroxysms of coughing or ventilation modes such as PEEP and HFJV, hemorrhagic fluids, refluxed or vomited gastric contents, to surgical debris. Accidental aspiration is not uncommon and occurs during the extubation proceedure and during periods of accidental cuff deflation or inappropriately low cuff inflation states. Pneumonia and other pathological conditions can result, leading to serious sequelae and prolonged and complicated hospitalization.
Effective removal of secretions and other accumulations is a clinical necessity, not only to prevent medical complications but also to meet the hygienic care and comfort needs of the patient. Attempts to remove these accumulations on the part of the patient by swallowing efforts contributes to the discomfort and irritation associated with intubation by causing muscular contractions around the tube and sliding movement between the tube and the wall of the intubated pathway. Consequently, injury can occur in areas of tube-tissue contact, particularly in the interarytenoid region, by such tube-tissue interaction. Inserting a suction catheter beside and along the tracheal tube wall is an additional source of discomfort and irritation as cough and gag reflexes are stimulated. Forceful contact between the catheter and tissue structure also occurs and suction entrapment of tissue by applied suction forces is unavoidable all of which is counterproductive, noxious, and traumatizing in effect. Furthermore, control of the suction catheter is difficult, making insertion of the catheter to the vicinity of the forward segment and cuff difficult to achieve. Often, as in the case of the orally or nasally intubated patent, the suction catheter is unintentionally inserted into the esophogus rather than following the more difficult path into the trachea.